That’s when the superstar presenters who will dazzle fans worldwide on Sunday practice walking onto the Dolby Theatre stage and delivering their lines in front of a small audience of show workers and rehearsal actors. Instead of glamorous gowns and tuxedos, most stars rock jeans and sneakers.

Will Smith’s sneakers were a shiny silvery-pink. Wearing a puffer vest, a thermal and jeans, Smith cracked up the crowd by reading his presentation in a jokey kid voice. During a second pass, he read normally, then declared: “I killed that one!”

When a pair of rehearsal actors stepped on stage to collect the award he was presenting, Smith pretended to toss them the prop Oscar used for rehearsals: a wooden version of the real thing.

Garner, who wore her show-day shoes with a blazer and jeans, offered some advice to first-time Oscar presenter Benedict Cumberbatch.

“This is my fifth or sixth (show),” she told him. “My first one was with Mickey Mouse, so I had to look at a green stick, as one does on live TV.”

She assured him he’d be great.

Jennifer Lawrence, who arrived wearing no makeup, all black clothing and her short hair slicked back, shimmied and waved as she walked out on stage. Afraid to read the contents of the prop winner’s envelope, she jokingly presented her award to Ryan Seacrest.

When told she was meant to actually read the name inside the envelope for rehearsal purposes, she confessed, “Oh, I didn’t know!”

She did, and when rehearsal actor came on stage to claim the prize, she hugged him.

Veteran presenter John Travolta also wore all black, from his jeans and tennis-shoes to his button-down shirt and ball cap.

“I was just about to get some popcorn,” said Oscar producer Neil Meron said when he spotted Travolta backstage. “And look who walks in: Mr. Popcorn himself!”

Kristen Bell and Michael B. Jordan needed a moment to collect themselves after looking at all the seat-saving placards in the audience that indicate exactly where the industry heavyweights will be sitting on Oscar night.

She wore towering platform heels on stage, but changed into a pair of sneakers as soon as she walked off.

Kerry Washington, who wore a loose white blouse over cropped jeans with sling-back silver stilettos, delighted the college students who will carry the Oscar trophies on stage when she greeted them before her rehearsal.

“I hope you’re having fun,” she told them. “There’s no stopping you!”

Channing Tatum, who helped select the students with Oscar producers, bonded with them backstage.

He showed them iPhone photos of his 9-month-old daughter, saying, “She’s just starting to get cute.” He also confessed that his Oscar debut last year, when he danced with Charlize Theron, was “the most nerve-racking thing ever.”

“I wish I could get in on this at y’all’s age,” he told the group of 19- to 22-year-olds. “Y’all have fun.”